State of Delaware DELAWARE GEOLOGICAL SURVEY Robert R. Jordan, State Geologist OPEN FILE REPORT NO. 37 SUMMARY REPORT THE COASTAL STORM OF DECEMBER 10-14,1992 DELAWARE AND MARYLAND By Kelvin W. Ramsey' John H. Talley' Darlene V. Wells2 'Delaware Geological Survey 2Maryland Geological Survey University of Delaware Newark, Delaware February 1993 CONTENTS Page CLIMATIC CONDITIONS FOR THE STORM OF DECEMBER 10-14,1992 . 1 GEOLOGIC OBSERVATIONS 19 SUMMARY 20 CONCLUSIONS ............................................... .. 22 GEOLOGIC OBSERVATIONS· MARYLAND. ...... .. .... .... .......... .. 24 ACKNOWLEDGMENTS. ......................................... .. 28 FIGURES Figure 1. Track of Storm - December 11-12, 1992. 2 Figure 2. Location of Weather and TIde Gage Stations. 3 Figure 3. TIde Gage Data. 10 Figure 4. Digital TIde Gage Station Records - December 9-15, 1992. ........ .. 16 Figure 5. Storm track locations and wind directions at the University of Delaware Agricultural Station near Georgetown, DE, January 4, 1992 and December 11-12, 1992. ................ .. 21 Figure 6. Location of profile lines within Assateague Island State Park.. 26 Figure 7. Pre- and post-storm beach profiles collected in Assateague Island State Park 27 TABLES Table 1. Precipitation Data - December 10-14, 1992 1 Table 2. Wind and Barometric Pressure Data - December 10-14, 1992 4 Table 3. Selected Predicted High and Low Tides -December 9-12, 1992. 9 Table 4. Maximum Heights of Tide ................................. .. 11 Table 5. Comparison of historical highest water levels and highest recorded levels during the December, 1992 storm.. 12 Table 6. Selected Tidal Stations - October 31, 1991, January 4, 1992, December 11, 12, 1992. 13 Table 7. Tidal Crest Stage Stations 14 Table 8. Wave heights and wave periods recorded during the December storm by the CERC wave gage located offshore Ocean City, Maryland 18 PREFACE The DGS (Delaware Geological Survey) regularly compiles and evaluates a variety of hydrologic and geologic data. Special efforts are made to obtain detailed measurements, sometimes under difficult conditions, during and following extreme events such as storms, floods, droughts, and earthquakes. Through rapid collection and dissemination of data, the DGS assists those agencies with emergency response responsibilities in evaluating and predicting conditions during specific events. Following such events, the DGS routinely compiles information and prepares reports and maps to help assess the nature and effects of events and to predict the impact of future ones. Although most such reports and maps are not formally published, they are available and are used by officials and citizens. The DGS encourages the exchange of data about such events collected by various agencies so that as complete record as possible may be assembled for use by each unit. This report represents the beginning of a cooperative effort with the Maryland Geological Survey to compile and report data for coastal storms that affect the upper Delmarva Peninsula. Data and observations from Maryland were provided by the Maryland Geological Survey and are included in this report. CLIMATIC CONDffiONS FOR THE STORM OF DECEMBER 10-14, 1992 Su=ary of Storm Activity! On December 10, a low pressure system moved rapidly north-northwest from eastern North Carolina and Virginia, up the Chesapeake Bay to a position just west of Chestertown in Kent County, Maryland by 0700 on December 11. The system then moved irregularly to the southeast, stalled for several hours over Georgetown, Delaware, and proceeded offshore early on December 12. Approximate locations of the storm's track are shown on Figure 1. The storm had associated rain that contributed to some local stream flooding and high winds that created strong surf and waves. The waves were compounded by an astronomical high tide (full moon) to produce coastal flooding along Delaware Bay and some breaching of the dunes along the Atlantic coast. The position of the storm offshore blew north-northeast winds onto the coast and abnormally high tides continued through December 15. The following tables (1-8) and figures (1-7) are compilations of data collected after the storm. Table 1. Precipitation Data - December 10-14, 1992 December 10 11 12 13 14 Total Location (inches) (inches) Salisbury, MD FAA - Airport 2.12 0.69 0.09 2.90 Assateague Island National Seashore Weather Station 1.60 0.13 0.Q3 1.76 Lewes, DE 0.17 1.62 0.06 0.05 T 1.90 Georgetown, DE (U of D) 0.00 1.60 0.25 0.21 2.06 Greenwood, DE 0.61 0.67 0.10 0.07 1.45 Dover Air Force Base 1.10 0.43 0.11 T 1.64 Dover, DE (DeIDOT) 0.06 1.48 0.09 0.07 0.03 1.73 New Castle, DE (NWS) 1.15 1.50 0.06 2.71 Porter Res., Wilmington, DE 1.03 1.47 0.61 0.01 3.12 1 Source of information: National Weather Service (NWS) 1 Figure 1. Track of Storm - December 11-12, 1992. N J.~ o IL-......"O--''----'--'-,·.~O-' ! I 1 K~ • I I wI ~I I j/ ~f -._----.._--------_.--------------_ .... 2 Figure 2. Location of Weather and Tide Gage Stations. .ljll~I..~,~'" I '"'_ e... ~ toUNlT •."'~rpl\T ""r'ijllli JIIW t'ASYl.E I \ , \,.---;;-;;~;~~- ,. D ill JUDDLETnH 3'.20' 11ll DonI b_""~" __..ll'J lilLI:' ,.J".'A..--' } 4. CEIl.UI c:DzX --m-- I JI'LI"OllP ... tllll:-~l" SUfJDlIl , _I' r-----;.../ , GKUHlrOOD , '.".~ ~ ~ ......,.... .. -. \ < lit SE.lI'ORD < ~ o o o , '!II , ,.."'" < 31.30' \ , '-- -- ---- ------ - -------- jHdU'li'IW-- -- WAR YL ... If D 3 Table 2. Wind and Barometric Pressure Data - December 10-14, 1992 u. s. Coast Guard Station University of Delaware Agricultural Station Indian River, DE Georgetown, DE Time Wind Wind Maximum Barometric TIme Wind Wind Maximum Barometric Date (ES1) Direction Velocity Gusts Pressure Date (ES1) Direction Velocity Gusts Pressure (mph) (mph) (mph) (mph) Dec 8 0700 NNW 9 30.11 Dec 8 0100 N31°W 7.8 13.2 29.99 0900 NNW 9 30.16 0400 N31°W 6.2 11.3 30.01 1200 NNW 9 30.17 0700 N4O"W 5.3 9.8 3005 1500 N 10 30.19 1000 N16"W 9.8 17.8 30.10 1800 NNW 10 30.20 1300 N27"W 9.4 19.3 30.06 2100 NNW 10 30.21 1600 N44°W 9.1 14.9 30.08 1900 N47"'W 4.1 7.3 30.13 2200 N1SoW 2.5 5.1 30.17 Dec 9 0800 N 13 30.33 Dec 9 0100 N25°E 6.3 11.4 30.21 1100 N 12 30.40 0400 N7"W 3.4 6.3 30.24 1400 NE 12 30.36 0700 NI5"W 4.1 6.3 30.28 1700 N 7 30.38 1000 N &7 15.6 30.34 2000 NE 7 30.38 1300 N21"E 10.9 18.2 30.28 1600 N48°E 4.6 8.3 30.28 1900 SSS"E 1.5 2.6 30.30 2200 N24"E 1.2 2.5 30.29 Dec 100600 SE 24 30.22 Dec 10 0100 N87°E 1.8 3.2 30.26 0900 SE 32 30.14 0400 N61°E 2.8 &2 30.21 1200 ESE 35 30.02 0700 S84"E 4.2 13.8 30.10 1500 SE 35 29.88 1000 S74"E 9.6 17.1 30.04 1800 SE 35 29.70 1300 576°E 17.0 27.8 29.86 2100 SE 46 29.48 1600 574°E 20.1 33.3 29.71 1900 578°E 21.6 34.5 29.54 2200 N87"'E 20.5 37.0 29.35 Dec 11 0600 SSW 12 29.22 Dec 11 0100 579°E 9.3 23.4 27.40 1000 S 13 29.20 0400 S25"W 9.8 16.9 29.16 1500 S 12 29.20 0500 S49"W 11.2 20.3 29.12 1800 SE 12 29.36 0700 S13°W 8.4 16.0 29.11 2100 S 12 29.36 0900 Sl1"E 7.8 14.4 29.10 1000 848°E 4.1 9.9 29.10 1300 8300 E 7.1 13.2 29.06 1400 54C1 E 9.1 14.9 29.07 1600 S63"E 6.5 10.9 29.12 1900 N41°E 3.5 6.4 29.21 2100 NsoE 5.6 9.3 29.26 Dec 120600 N 23 29.62 Dec 120300 NI9"E 11.2 20.2 29.45 0900 N 23 29.70 0500 N23"E 14.6 23.4 29.52 1200 N 23 29.71 0600 NI4"E 15.4 24.7 29.55 1500 N 23 29.74 0700 N9"E 14.5 26.4 29.59 1800 N 23 29.80 1000 NloE 13.6 25.0 29.68 2100 N 26 29.86 1300 N2°E 14.6 27.2 29.67 1600 NI5"W 15.8 26.3 29.69 1900 N 14.5 26.1 29.76 2200 N2"E 13.5 22.7 29.83 4 Table 2 (continued). U. S. Coast Guard Station University of Delaware Agricultural Station Indian River, DE George-., DE Time Wind Wind Maximum Barometric Time Wind Wind Maximum Barometric Date (ES1) Direction Velocity Gusts Pressure Date (ES1) Direction Velocity Gusts Pressure (mph) (mph) (mph) (mph) oo N 23 29.95 Dec 13 0100 N3°E 13.3 23.7 29.87סס Dec 13 0600 N 17 30.07 0400 N3°E 128 21.9 29.91 0900 N 17 30.09 0700 N9"E 10.6 18.9 29.98 1200 N 21 30.17 1000 NlloE 122 20.7 30.06 1500 N 23 30.18 1300 N4°E 10.5 17.6 30.07 1800 NNE 29 30.25 1600 N2SoE 11.5 20.9 30.11 2100 NNE 29 30.28 1900 N21°E 10.6 17.2 30.10 2200 N29"E 13.4 20.7 30.22 Dec 140700 N 23 30.31 Dec 14 0100 N21°E 9.3 18.1 30.22 0800 N 23 30.39 0400 N25°E 10.6 16.8 30.24 1300 N 14 30.34 0700 NI3°E 9.5 16.2 30.26 1800 N 16 30.32 1000 NI6°E 8.6 13.0 30.30 1300 NI8°E 9.6 15.9 30.28 1600 NSoE 7.5 13.1 30.26 1900 N14°E 6.5 9.8 30.28 2200 NsoE 4.9 7.6 30.27 Dec 15 0500 N 13 30.32 Dec 15 0100 N31"W 4.6 7.8 30.26 0800 N 9 30.32 0400 N36°W 3.6 6.9 30.24 1100 NW 8 30.34 0700 N43°W 25 6.8 3024 1000 N52·W 5.3 8.5 30.26 Dover Air Force Base National Weather Service Office Dover, DE New Castle, DE Tune Wind Wind Maximum Barometric TIme Wind Wind Maximum Barometric Date (ES1) Direction Velocity Gusts Pressure Date (ES1) Direction Velocity Gusts Pressure (mph) (mph) (mph) (mph) Dec 9 0055 N 10 30.275 Dec 10 0051 N800E 6 30.37 0355 NIO·W 5 30.300 0351 N7O"E 9 30.34 0655 N300W 5 30.355 0652 N70"E 8 30.25 0955 NI0·W 13 30.400 0950 N70G E 12 30.18 1255 N200E 12 30.340 1252 N600E 16 30.01 1555 N200W 5 30.355 1550 SSOoE 23 32 29.84 1855 N200E 2 30.350 1852 SSOoE 20 31 29.74 2155 N500E 6 30.345 2152 N700E 18 32 29.56 Dec 100055 N600E 6 30.315 Dec 11 0050 N700E 23 40 29.39 0355 N500E 8 30.270 0353 N70·E 25 37 29.33 0655 N800E 10 30.170 0650 N500E 18 32 29.23 0955 S70"E 14 21 30.115 0950 N500E 29 40 29.24 1255 S80"E 12 23 29.935 1142 N300E 21 31 29.19 1555 S70"E 18 37 29.780 1252 N500E 15 28 29.20 18S5 E 18 36 29.645 1550 N500E 14 29.31 2155 N800E 23 37 29.450 1851 N400E 18 24 29.40 2151 N500E 15 21 29.50 5 Table 2 (continued).